From: Robin Murphy <robin.murphy@arm.com>
So far our parsing of {iommu,msi}-map properites has always blindly
asusmed that the output specifiers will always have exactly 1 cell.
This typically does happen to be the case, but is not actually enforced
(and the PCI msi-map binding even explicitly states support for 0 or 1
cells) - as a result we've now ended up with dodgy DTs out in the field
which depend on this behaviour to map a 1-cell specifier for a 2-cell
provider, despite that being bogus per the bindings themselves.
Since there is some potential use in being able to map at least single
input IDs to multi-cell output specifiers (and properly support 0-cell
outputs as well), add support for properly parsing and using the target
nodes' #cells values, albeit with the unfortunate complication of still
having to work around expectations of the old behaviour too.
Since there are multi-cell output specifiers, the callers of of_map_id()
may need to get the exact cell output value for further processing.
Added support for that part --charan
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
---
drivers/iommu/of_iommu.c | 3 +-
drivers/of/base.c | 107 ++++++++++++++++++++++++++++++---------
include/linux/of.h | 17 ++++---
3 files changed, 94 insertions(+), 33 deletions(-)
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index eac62bc441c5..48759cf1d900 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -45,10 +45,11 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
struct device *dev,
const u32 *id)
{
- struct of_phandle_args iommu_spec = { .args_count = 1 };
+ struct of_phandle_args iommu_spec = {};
struct of_map_id_arg arg = {
.target = &iommu_spec.np,
.id_out = iommu_spec.args,
+ .map_cells = &iommu_spec.args_count,
};
int err;
diff --git a/drivers/of/base.c b/drivers/of/base.c
index b8f78a9e6a09..68a7d6ddba66 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2045,11 +2045,30 @@ int of_find_last_cache_level(unsigned int cpu)
return cache_level;
}
+/*
+ * Some DTs have an iommu-map targeting a 2-cell IOMMU node while
+ * specifying only 1 cell. Fortunately they all consist of length == 1
+ * entries with the same target, so check for that pattern.
+ */
+static bool of_check_bad_map(const __be32 *map, int len)
+{
+ __be32 phandle = map[1];
+
+ if (len % 4)
+ return false;
+ for (int i = 0; i < len; i += 4) {
+ if (map[i + 1] != phandle || map[i + 3] != cpu_to_be32(1))
+ return false;
+ }
+ return true;
+}
+
/**
* of_map_id - Translate an ID through a downstream mapping.
* @np: root complex device node.
* @id: device ID to map.
* @map_name: property name of the map to use.
+ * @cells_name: property name of target specifier cells.
* @map_mask_name: optional property name of the mask to use.
* @arg: contains the optional params, @target which is a pointer
* to the target device node and id_out which is a pointer
@@ -2065,18 +2084,19 @@ int of_find_last_cache_level(unsigned int cpu)
*
* Return: 0 on success or a standard error code on failure.
*/
-int of_map_id(const struct device_node *np, u32 id,
- const char *map_name, const char *map_mask_name,
- struct of_map_id_arg *arg)
+int of_map_id(const struct device_node *np, u32 id, const char *map_name,
+ const char *cells_name, const char *map_mask_name,
+ struct of_map_id_arg *arg)
{
u32 map_mask, masked_id;
- int map_len;
+ int map_bytes, map_len, offset = 0;
+ bool bad_map = false;
const __be32 *map = NULL;
if (!np || !map_name || !arg || (!arg->target && !arg->id_out))
return -EINVAL;
- map = of_get_property(np, map_name, &map_len);
+ map = of_get_property(np, map_name, &map_bytes);
if (!map) {
if (arg->target)
return -ENODEV;
@@ -2085,11 +2105,9 @@ int of_map_id(const struct device_node *np, u32 id,
return 0;
}
- if (!map_len || map_len % (4 * sizeof(*map))) {
- pr_err("%pOF: Error: Bad %s length: %d\n", np,
- map_name, map_len);
- return -EINVAL;
- }
+ if (map_bytes % sizeof(*map))
+ goto err_map_len;
+ map_len = map_bytes / sizeof(*map);
/* The default is to select all bits. */
map_mask = 0xffffffff;
@@ -2102,27 +2120,62 @@ int of_map_id(const struct device_node *np, u32 id,
of_property_read_u32(np, map_mask_name, &map_mask);
masked_id = map_mask & id;
- for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
+ while (offset < map_len) {
struct device_node *phandle_node;
- u32 id_base = be32_to_cpup(map + 0);
- u32 phandle = be32_to_cpup(map + 1);
- u32 out_base = be32_to_cpup(map + 2);
- u32 id_len = be32_to_cpup(map + 3);
+ u32 id_base, phandle, cells, id_len, id_off;
+ const __be32 *out_base;
+
+ if (map_len - offset < 2)
+ goto err_map_len;
+ id_base = be32_to_cpup(map + offset);
if (id_base & ~map_mask) {
- pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores id-base (0x%x)\n",
- np, map_name, map_name,
+ pr_err("%pOF: Invalid %s translation - %s (0x%x) ignores id-base (0x%x)\n",
+ np, map_name, map_mask_name,
map_mask, id_base);
return -EFAULT;
}
- if (masked_id < id_base || masked_id >= id_base + id_len)
- continue;
-
+ phandle = be32_to_cpup(map + offset + 1);
phandle_node = of_find_node_by_phandle(phandle);
if (!phandle_node)
return -ENODEV;
+ if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
+ pr_err("%pOF: missing %s property\n", phandle_node, cells_name);
+ return -EINVAL;
+ }
+
+ if (map_len - offset < 3 + cells)
+ goto err_map_len;
+
+ if (offset == 0 && cells == 2) {
+ bad_map = of_check_bad_map(map, map_len);
+ if (bad_map) {
+ pr_warn_once("%pOF: %s mismatches target %s, assuming extra cell of 0\n",
+ np, map_name, cells_name);
+ cells = 1;
+ }
+ }
+
+ out_base = map + offset + 2;
+ offset += 3 + cells;
+
+ id_len = be32_to_cpup(map + offset - 1);
+ if (id_len > 1 && cells > 1) {
+ /*
+ * With 1 output cell we reasonably assume its value
+ * has a linear relationship to the input; with more,
+ * we'd need help from the provider to know what to do.
+ */
+ pr_err("%pOF: Unsupported %s - cannot handle %d-ID range with %d-cell output specifier\n",
+ np, map_name, id_len, cells);
+ return -EINVAL;
+ }
+ id_off = masked_id - id_base;
+ if (masked_id < id_base || id_off >= id_len)
+ continue;
+
if (arg->target) {
if (*arg->target)
of_node_put(phandle_node);
@@ -2133,12 +2186,14 @@ int of_map_id(const struct device_node *np, u32 id,
continue;
}
- if (arg->id_out)
- *arg->id_out = masked_id - id_base + out_base;
+ for (int i = 0; arg->id_out && i < cells; i++)
+ arg->id_out[i] = id_off + be32_to_cpu(out_base[i]);
+ if (arg->map_cells)
+ *arg->map_cells = cells;
pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
- np, map_name, map_mask, id_base, out_base,
- id_len, id, masked_id - id_base + out_base);
+ np, map_name, map_mask, id_base, be32_to_cpup(out_base),
+ id_len, id, id_off + be32_to_cpup(out_base));
return 0;
}
@@ -2149,5 +2204,9 @@ int of_map_id(const struct device_node *np, u32 id,
if (arg->id_out)
*arg->id_out = id;
return 0;
+
+err_map_len:
+ pr_err("%pOF: Error: Bad %s length: %d\n", np, map_name, map_bytes);
+ return -EINVAL;
}
EXPORT_SYMBOL_GPL(of_map_id);
diff --git a/include/linux/of.h b/include/linux/of.h
index 21bdce2b37ca..1981509c7918 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -29,6 +29,7 @@ struct device_node;
struct of_map_id_arg {
struct device_node **target;
u32 *id_out;
+ u32 *map_cells;
};
struct property {
@@ -462,9 +463,9 @@ const char *of_prop_next_string(const struct property *prop, const char *cur);
bool of_console_check(const struct device_node *dn, char *name, int index);
-int of_map_id(const struct device_node *np, u32 id,
- const char *map_name, const char *map_mask_name,
- struct of_map_id_arg *arg);
+int of_map_id(const struct device_node *np, u32 id, const char *map_name,
+ const char *cells_name, const char *map_mask_name,
+ struct of_map_id_arg *arg);
phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
@@ -911,9 +912,9 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag
{
}
-static inline int of_map_id(const struct device_node *np, u32 id,
- const char *map_name, const char *map_mask_name,
- struct of_map_id_arg *arg)
+static inline int of_map_id(const struct device_node *np, u32 id, const char *map_name,
+ const char *cells_name, const char *map_mask_name,
+ struct of_map_id_arg *arg);
{
return -EINVAL;
}
@@ -1444,7 +1445,7 @@ static inline int of_property_read_s32(const struct device_node *np,
static inline int of_map_iommu_id(const struct device_node *np, u32 id,
struct of_map_id_arg *arg)
{
- return of_map_id(np, id, "iommu-map", "iommu-map-mask", arg);
+ return of_map_id(np, id, "iommu-map", "#iommu-cells", "iommu-map-mask", arg);
}
static inline int of_map_msi_id(const struct device_node *np, u32 id,
@@ -1455,7 +1456,7 @@ static inline int of_map_msi_id(const struct device_node *np, u32 id,
.id_out = id_out,
};
- return of_map_id(np, id, "msi-map", "msi-map-mask", &arg);
+ return of_map_id(np, id, "msi-map", "#msi-cells", "msi-map-mask", &arg);
}
#define of_for_each_phandle(it, err, np, ln, cn, cc) \
--
2.34.1On Thu, Dec 04, 2025 at 03:25:30PM +0530, Vijayanand Jitta wrote:
> From: Robin Murphy <robin.murphy@arm.com>
>
> So far our parsing of {iommu,msi}-map properites has always blindly
> asusmed that the output specifiers will always have exactly 1 cell.
> This typically does happen to be the case, but is not actually enforced
> (and the PCI msi-map binding even explicitly states support for 0 or 1
> cells) - as a result we've now ended up with dodgy DTs out in the field
> which depend on this behaviour to map a 1-cell specifier for a 2-cell
> provider, despite that being bogus per the bindings themselves.
>
> Since there is some potential use in being able to map at least single
> input IDs to multi-cell output specifiers (and properly support 0-cell
> outputs as well), add support for properly parsing and using the target
> nodes' #cells values, albeit with the unfortunate complication of still
> having to work around expectations of the old behaviour too.
>
> Since there are multi-cell output specifiers, the callers of of_map_id()
> may need to get the exact cell output value for further processing.
> Added support for that part --charan
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
> ---
> drivers/iommu/of_iommu.c | 3 +-
> drivers/of/base.c | 107 ++++++++++++++++++++++++++++++---------
> include/linux/of.h | 17 ++++---
> 3 files changed, 94 insertions(+), 33 deletions(-)
>
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> index eac62bc441c5..48759cf1d900 100644
> --- a/drivers/iommu/of_iommu.c
> +++ b/drivers/iommu/of_iommu.c
> @@ -45,10 +45,11 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
> struct device *dev,
> const u32 *id)
> {
> - struct of_phandle_args iommu_spec = { .args_count = 1 };
> + struct of_phandle_args iommu_spec = {};
> struct of_map_id_arg arg = {
> .target = &iommu_spec.np,
> .id_out = iommu_spec.args,
> + .map_cells = &iommu_spec.args_count,
> };
> int err;
>
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index b8f78a9e6a09..68a7d6ddba66 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -2045,11 +2045,30 @@ int of_find_last_cache_level(unsigned int cpu)
> return cache_level;
> }
>
> +/*
> + * Some DTs have an iommu-map targeting a 2-cell IOMMU node while
> + * specifying only 1 cell. Fortunately they all consist of length == 1
> + * entries with the same target, so check for that pattern.
Can you show what a bad entry looks like here.
> + */
> +static bool of_check_bad_map(const __be32 *map, int len)
> +{
> + __be32 phandle = map[1];
> +
> + if (len % 4)
> + return false;
> + for (int i = 0; i < len; i += 4) {
> + if (map[i + 1] != phandle || map[i + 3] != cpu_to_be32(1))
Why does the IOMMU arg cell have to be 1? The description said 'same
target', but it is just all have an IOMMU cell value of 1?
> + return false;
> + }
> + return true;
> +}
> +
> /**
> * of_map_id - Translate an ID through a downstream mapping.
> * @np: root complex device node.
> * @id: device ID to map.
> * @map_name: property name of the map to use.
> + * @cells_name: property name of target specifier cells.
> * @map_mask_name: optional property name of the mask to use.
> * @arg: contains the optional params, @target which is a pointer
> * to the target device node and id_out which is a pointer
> @@ -2065,18 +2084,19 @@ int of_find_last_cache_level(unsigned int cpu)
> *
> * Return: 0 on success or a standard error code on failure.
> */
> -int of_map_id(const struct device_node *np, u32 id,
> - const char *map_name, const char *map_mask_name,
> - struct of_map_id_arg *arg)
> +int of_map_id(const struct device_node *np, u32 id, const char *map_name,
> + const char *cells_name, const char *map_mask_name,
> + struct of_map_id_arg *arg)
> {
> u32 map_mask, masked_id;
> - int map_len;
> + int map_bytes, map_len, offset = 0;
> + bool bad_map = false;
> const __be32 *map = NULL;
>
> if (!np || !map_name || !arg || (!arg->target && !arg->id_out))
> return -EINVAL;
>
> - map = of_get_property(np, map_name, &map_len);
> + map = of_get_property(np, map_name, &map_bytes);
> if (!map) {
> if (arg->target)
> return -ENODEV;
> @@ -2085,11 +2105,9 @@ int of_map_id(const struct device_node *np, u32 id,
> return 0;
> }
>
> - if (!map_len || map_len % (4 * sizeof(*map))) {
> - pr_err("%pOF: Error: Bad %s length: %d\n", np,
> - map_name, map_len);
> - return -EINVAL;
> - }
> + if (map_bytes % sizeof(*map))
> + goto err_map_len;
> + map_len = map_bytes / sizeof(*map);
>
> /* The default is to select all bits. */
> map_mask = 0xffffffff;
> @@ -2102,27 +2120,62 @@ int of_map_id(const struct device_node *np, u32 id,
> of_property_read_u32(np, map_mask_name, &map_mask);
>
> masked_id = map_mask & id;
> - for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
> + while (offset < map_len) {
> struct device_node *phandle_node;
> - u32 id_base = be32_to_cpup(map + 0);
> - u32 phandle = be32_to_cpup(map + 1);
> - u32 out_base = be32_to_cpup(map + 2);
> - u32 id_len = be32_to_cpup(map + 3);
> + u32 id_base, phandle, cells, id_len, id_off;
> + const __be32 *out_base;
> +
> + if (map_len - offset < 2)
> + goto err_map_len;
>
> + id_base = be32_to_cpup(map + offset);
> if (id_base & ~map_mask) {
> - pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores id-base (0x%x)\n",
> - np, map_name, map_name,
> + pr_err("%pOF: Invalid %s translation - %s (0x%x) ignores id-base (0x%x)\n",
> + np, map_name, map_mask_name,
> map_mask, id_base);
> return -EFAULT;
> }
>
> - if (masked_id < id_base || masked_id >= id_base + id_len)
> - continue;
> -
> + phandle = be32_to_cpup(map + offset + 1);
> phandle_node = of_find_node_by_phandle(phandle);
> if (!phandle_node)
> return -ENODEV;
>
> + if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
> + pr_err("%pOF: missing %s property\n", phandle_node, cells_name);
> + return -EINVAL;
> + }
> +
> + if (map_len - offset < 3 + cells)
> + goto err_map_len;
> +
> + if (offset == 0 && cells == 2) {
> + bad_map = of_check_bad_map(map, map_len);
> + if (bad_map) {
> + pr_warn_once("%pOF: %s mismatches target %s, assuming extra cell of 0\n",
> + np, map_name, cells_name);
> + cells = 1;
> + }
> + }
> +
> + out_base = map + offset + 2;
> + offset += 3 + cells;
> +
> + id_len = be32_to_cpup(map + offset - 1);
> + if (id_len > 1 && cells > 1) {
> + /*
> + * With 1 output cell we reasonably assume its value
> + * has a linear relationship to the input; with more,
> + * we'd need help from the provider to know what to do.
> + */
> + pr_err("%pOF: Unsupported %s - cannot handle %d-ID range with %d-cell output specifier\n",
> + np, map_name, id_len, cells);
> + return -EINVAL;
> + }
> + id_off = masked_id - id_base;
> + if (masked_id < id_base || id_off >= id_len)
> + continue;
> +
> if (arg->target) {
> if (*arg->target)
> of_node_put(phandle_node);
> @@ -2133,12 +2186,14 @@ int of_map_id(const struct device_node *np, u32 id,
> continue;
> }
>
> - if (arg->id_out)
> - *arg->id_out = masked_id - id_base + out_base;
> + for (int i = 0; arg->id_out && i < cells; i++)
> + arg->id_out[i] = id_off + be32_to_cpu(out_base[i]);
>
> + if (arg->map_cells)
> + *arg->map_cells = cells;
> pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
> - np, map_name, map_mask, id_base, out_base,
> - id_len, id, masked_id - id_base + out_base);
> + np, map_name, map_mask, id_base, be32_to_cpup(out_base),
> + id_len, id, id_off + be32_to_cpup(out_base));
> return 0;
> }
>
> @@ -2149,5 +2204,9 @@ int of_map_id(const struct device_node *np, u32 id,
> if (arg->id_out)
> *arg->id_out = id;
> return 0;
> +
> +err_map_len:
> + pr_err("%pOF: Error: Bad %s length: %d\n", np, map_name, map_bytes);
> + return -EINVAL;
> }
> EXPORT_SYMBOL_GPL(of_map_id);
> diff --git a/include/linux/of.h b/include/linux/of.h
> index 21bdce2b37ca..1981509c7918 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -29,6 +29,7 @@ struct device_node;
> struct of_map_id_arg {
> struct device_node **target;
> u32 *id_out;
> + u32 *map_cells;
> };
>
> struct property {
> @@ -462,9 +463,9 @@ const char *of_prop_next_string(const struct property *prop, const char *cur);
>
> bool of_console_check(const struct device_node *dn, char *name, int index);
>
> -int of_map_id(const struct device_node *np, u32 id,
> - const char *map_name, const char *map_mask_name,
> - struct of_map_id_arg *arg);
> +int of_map_id(const struct device_node *np, u32 id, const char *map_name,
> + const char *cells_name, const char *map_mask_name,
> + struct of_map_id_arg *arg);
>
> phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
>
> @@ -911,9 +912,9 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag
> {
> }
>
> -static inline int of_map_id(const struct device_node *np, u32 id,
> - const char *map_name, const char *map_mask_name,
> - struct of_map_id_arg *arg)
> +static inline int of_map_id(const struct device_node *np, u32 id, const char *map_name,
> + const char *cells_name, const char *map_mask_name,
> + struct of_map_id_arg *arg);
> {
> return -EINVAL;
> }
> @@ -1444,7 +1445,7 @@ static inline int of_property_read_s32(const struct device_node *np,
> static inline int of_map_iommu_id(const struct device_node *np, u32 id,
> struct of_map_id_arg *arg)
> {
> - return of_map_id(np, id, "iommu-map", "iommu-map-mask", arg);
> + return of_map_id(np, id, "iommu-map", "#iommu-cells", "iommu-map-mask", arg);
> }
>
> static inline int of_map_msi_id(const struct device_node *np, u32 id,
> @@ -1455,7 +1456,7 @@ static inline int of_map_msi_id(const struct device_node *np, u32 id,
> .id_out = id_out,
> };
>
> - return of_map_id(np, id, "msi-map", "msi-map-mask", &arg);
> + return of_map_id(np, id, "msi-map", "#msi-cells", "msi-map-mask", &arg);
There are cases of no #msi-cells and we default to 0 cells in that case.
Do you maintain that?
Rob
On 12/10/2025 1:47 AM, Rob Herring wrote:
> On Thu, Dec 04, 2025 at 03:25:30PM +0530, Vijayanand Jitta wrote:
>> From: Robin Murphy <robin.murphy@arm.com>
>>
>> So far our parsing of {iommu,msi}-map properites has always blindly
>> asusmed that the output specifiers will always have exactly 1 cell.
>> This typically does happen to be the case, but is not actually enforced
>> (and the PCI msi-map binding even explicitly states support for 0 or 1
>> cells) - as a result we've now ended up with dodgy DTs out in the field
>> which depend on this behaviour to map a 1-cell specifier for a 2-cell
>> provider, despite that being bogus per the bindings themselves.
>>
>> Since there is some potential use in being able to map at least single
>> input IDs to multi-cell output specifiers (and properly support 0-cell
>> outputs as well), add support for properly parsing and using the target
>> nodes' #cells values, albeit with the unfortunate complication of still
>> having to work around expectations of the old behaviour too.
>>
>> Since there are multi-cell output specifiers, the callers of of_map_id()
>> may need to get the exact cell output value for further processing.
>> Added support for that part --charan
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
>> ---
>> drivers/iommu/of_iommu.c | 3 +-
>> drivers/of/base.c | 107 ++++++++++++++++++++++++++++++---------
>> include/linux/of.h | 17 ++++---
>> 3 files changed, 94 insertions(+), 33 deletions(-)
>>
>> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
>> index eac62bc441c5..48759cf1d900 100644
>> --- a/drivers/iommu/of_iommu.c
>> +++ b/drivers/iommu/of_iommu.c
>> @@ -45,10 +45,11 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
>> struct device *dev,
>> const u32 *id)
>> {
>> - struct of_phandle_args iommu_spec = { .args_count = 1 };
>> + struct of_phandle_args iommu_spec = {};
>> struct of_map_id_arg arg = {
>> .target = &iommu_spec.np,
>> .id_out = iommu_spec.args,
>> + .map_cells = &iommu_spec.args_count,
>> };
>> int err;
>>
>> diff --git a/drivers/of/base.c b/drivers/of/base.c
>> index b8f78a9e6a09..68a7d6ddba66 100644
>> --- a/drivers/of/base.c
>> +++ b/drivers/of/base.c
>> @@ -2045,11 +2045,30 @@ int of_find_last_cache_level(unsigned int cpu)
>> return cache_level;
>> }
>>
>> +/*
>> + * Some DTs have an iommu-map targeting a 2-cell IOMMU node while
>> + * specifying only 1 cell. Fortunately they all consist of length == 1
>> + * entries with the same target, so check for that pattern.
>
> Can you show what a bad entry looks like here.
>
Sure, will add an example in the comments. Basically it would look like below.
for iommu with iommu-cells = <2>;
Device having below iommu-map property.
iommu-map = <0x0000 &smmu 0x0000 0x1>,
<0x0100 &smmu 0x0100 0x1>;
>> + */
>> +static bool of_check_bad_map(const __be32 *map, int len)
>> +{
>> + __be32 phandle = map[1];
>> +
>> + if (len % 4)
>> + return false;
>> + for (int i = 0; i < len; i += 4) {
>> + if (map[i + 1] != phandle || map[i + 3] != cpu_to_be32(1))
>
> Why does the IOMMU arg cell have to be 1? The description said 'same
> target', but it is just all have an IOMMU cell value of 1?
>
Here, the check is for length argument to be 1. This is to maintain backward
compatibility as mentioned above, as all such bad entries right now have
length as 1.
>> + return false;
>> + }
>> + return true;
>> +}
>> +
>> /**
>> * of_map_id - Translate an ID through a downstream mapping.
>> * @np: root complex device node.
>> * @id: device ID to map.
>> * @map_name: property name of the map to use.
>> + * @cells_name: property name of target specifier cells.
>> * @map_mask_name: optional property name of the mask to use.
>> * @arg: contains the optional params, @target which is a pointer
>> * to the target device node and id_out which is a pointer
>> @@ -2065,18 +2084,19 @@ int of_find_last_cache_level(unsigned int cpu)
>> *
>> * Return: 0 on success or a standard error code on failure.
>> */
>> -int of_map_id(const struct device_node *np, u32 id,
>> - const char *map_name, const char *map_mask_name,
>> - struct of_map_id_arg *arg)
>> +int of_map_id(const struct device_node *np, u32 id, const char *map_name,
>> + const char *cells_name, const char *map_mask_name,
>> + struct of_map_id_arg *arg)
>> {
>> u32 map_mask, masked_id;
>> - int map_len;
>> + int map_bytes, map_len, offset = 0;
>> + bool bad_map = false;
>> const __be32 *map = NULL;
>>
>> if (!np || !map_name || !arg || (!arg->target && !arg->id_out))
>> return -EINVAL;
>>
>> - map = of_get_property(np, map_name, &map_len);
>> + map = of_get_property(np, map_name, &map_bytes);
>> if (!map) {
>> if (arg->target)
>> return -ENODEV;
>> @@ -2085,11 +2105,9 @@ int of_map_id(const struct device_node *np, u32 id,
>> return 0;
>> }
>>
>> - if (!map_len || map_len % (4 * sizeof(*map))) {
>> - pr_err("%pOF: Error: Bad %s length: %d\n", np,
>> - map_name, map_len);
>> - return -EINVAL;
>> - }
>> + if (map_bytes % sizeof(*map))
>> + goto err_map_len;
>> + map_len = map_bytes / sizeof(*map);
>>
>> /* The default is to select all bits. */
>> map_mask = 0xffffffff;
>> @@ -2102,27 +2120,62 @@ int of_map_id(const struct device_node *np, u32 id,
>> of_property_read_u32(np, map_mask_name, &map_mask);
>>
>> masked_id = map_mask & id;
>> - for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
>> + while (offset < map_len) {
>> struct device_node *phandle_node;
>> - u32 id_base = be32_to_cpup(map + 0);
>> - u32 phandle = be32_to_cpup(map + 1);
>> - u32 out_base = be32_to_cpup(map + 2);
>> - u32 id_len = be32_to_cpup(map + 3);
>> + u32 id_base, phandle, cells, id_len, id_off;
>> + const __be32 *out_base;
>> +
>> + if (map_len - offset < 2)
>> + goto err_map_len;
>>
>> + id_base = be32_to_cpup(map + offset);
>> if (id_base & ~map_mask) {
>> - pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores id-base (0x%x)\n",
>> - np, map_name, map_name,
>> + pr_err("%pOF: Invalid %s translation - %s (0x%x) ignores id-base (0x%x)\n",
>> + np, map_name, map_mask_name,
>> map_mask, id_base);
>> return -EFAULT;
>> }
>>
>> - if (masked_id < id_base || masked_id >= id_base + id_len)
>> - continue;
>> -
>> + phandle = be32_to_cpup(map + offset + 1);
>> phandle_node = of_find_node_by_phandle(phandle);
>> if (!phandle_node)
>> return -ENODEV;
>>
>> + if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
>> + pr_err("%pOF: missing %s property\n", phandle_node, cells_name);
>> + return -EINVAL;
>> + }
>> +
>> + if (map_len - offset < 3 + cells)
>> + goto err_map_len;
>> +
>> + if (offset == 0 && cells == 2) {
>> + bad_map = of_check_bad_map(map, map_len);
>> + if (bad_map) {
>> + pr_warn_once("%pOF: %s mismatches target %s, assuming extra cell of 0\n",
>> + np, map_name, cells_name);
>> + cells = 1;
>> + }
>> + }
>> +
>> + out_base = map + offset + 2;
>> + offset += 3 + cells;
>> +
>> + id_len = be32_to_cpup(map + offset - 1);
>> + if (id_len > 1 && cells > 1) {
>> + /*
>> + * With 1 output cell we reasonably assume its value
>> + * has a linear relationship to the input; with more,
>> + * we'd need help from the provider to know what to do.
>> + */
>> + pr_err("%pOF: Unsupported %s - cannot handle %d-ID range with %d-cell output specifier\n",
>> + np, map_name, id_len, cells);
>> + return -EINVAL;
>> + }
>> + id_off = masked_id - id_base;
>> + if (masked_id < id_base || id_off >= id_len)
>> + continue;
>> +
>> if (arg->target) {
>> if (*arg->target)
>> of_node_put(phandle_node);
>> @@ -2133,12 +2186,14 @@ int of_map_id(const struct device_node *np, u32 id,
>> continue;
>> }
>>
>> - if (arg->id_out)
>> - *arg->id_out = masked_id - id_base + out_base;
>> + for (int i = 0; arg->id_out && i < cells; i++)
>> + arg->id_out[i] = id_off + be32_to_cpu(out_base[i]);
>>
>> + if (arg->map_cells)
>> + *arg->map_cells = cells;
>> pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
>> - np, map_name, map_mask, id_base, out_base,
>> - id_len, id, masked_id - id_base + out_base);
>> + np, map_name, map_mask, id_base, be32_to_cpup(out_base),
>> + id_len, id, id_off + be32_to_cpup(out_base));
>> return 0;
>> }
>>
>> @@ -2149,5 +2204,9 @@ int of_map_id(const struct device_node *np, u32 id,
>> if (arg->id_out)
>> *arg->id_out = id;
>> return 0;
>> +
>> +err_map_len:
>> + pr_err("%pOF: Error: Bad %s length: %d\n", np, map_name, map_bytes);
>> + return -EINVAL;
>> }
>> EXPORT_SYMBOL_GPL(of_map_id);
>> diff --git a/include/linux/of.h b/include/linux/of.h
>> index 21bdce2b37ca..1981509c7918 100644
>> --- a/include/linux/of.h
>> +++ b/include/linux/of.h
>> @@ -29,6 +29,7 @@ struct device_node;
>> struct of_map_id_arg {
>> struct device_node **target;
>> u32 *id_out;
>> + u32 *map_cells;
>> };
>>
>> struct property {
>> @@ -462,9 +463,9 @@ const char *of_prop_next_string(const struct property *prop, const char *cur);
>>
>> bool of_console_check(const struct device_node *dn, char *name, int index);
>>
>> -int of_map_id(const struct device_node *np, u32 id,
>> - const char *map_name, const char *map_mask_name,
>> - struct of_map_id_arg *arg);
>> +int of_map_id(const struct device_node *np, u32 id, const char *map_name,
>> + const char *cells_name, const char *map_mask_name,
>> + struct of_map_id_arg *arg);
>>
>> phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
>>
>> @@ -911,9 +912,9 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag
>> {
>> }
>>
>> -static inline int of_map_id(const struct device_node *np, u32 id,
>> - const char *map_name, const char *map_mask_name,
>> - struct of_map_id_arg *arg)
>> +static inline int of_map_id(const struct device_node *np, u32 id, const char *map_name,
>> + const char *cells_name, const char *map_mask_name,
>> + struct of_map_id_arg *arg);
>> {
>> return -EINVAL;
>> }
>> @@ -1444,7 +1445,7 @@ static inline int of_property_read_s32(const struct device_node *np,
>> static inline int of_map_iommu_id(const struct device_node *np, u32 id,
>> struct of_map_id_arg *arg)
>> {
>> - return of_map_id(np, id, "iommu-map", "iommu-map-mask", arg);
>> + return of_map_id(np, id, "iommu-map", "#iommu-cells", "iommu-map-mask", arg);
>> }
>>
>> static inline int of_map_msi_id(const struct device_node *np, u32 id,
>> @@ -1455,7 +1456,7 @@ static inline int of_map_msi_id(const struct device_node *np, u32 id,
>> .id_out = id_out,
>> };
>>
>> - return of_map_id(np, id, "msi-map", "msi-map-mask", &arg);
>> + return of_map_id(np, id, "msi-map", "#msi-cells", "msi-map-mask", &arg);
>
> There are cases of no #msi-cells and we default to 0 cells in that case.
> Do you maintain that?
>
> Rob
Thanks for pointing this, I see this case of no #msi-cells is not covered. Will
add it in next revision. Also, IIUC shouldn't we set default cells to '1' to
maintain backward compatibility of of_map_id in this case ? No ?
Thanks,
Vijay
On Wed, Dec 10, 2025 at 03:57:56PM +0530, Vijayanand Jitta wrote:
> On 12/10/2025 1:47 AM, Rob Herring wrote:
> > On Thu, Dec 04, 2025 at 03:25:30PM +0530, Vijayanand Jitta wrote:
> >> From: Robin Murphy <robin.murphy@arm.com>
> >>
> >> So far our parsing of {iommu,msi}-map properites has always blindly
> >> asusmed that the output specifiers will always have exactly 1 cell.
> >> This typically does happen to be the case, but is not actually enforced
> >> (and the PCI msi-map binding even explicitly states support for 0 or 1
> >> cells) - as a result we've now ended up with dodgy DTs out in the field
> >> which depend on this behaviour to map a 1-cell specifier for a 2-cell
> >> provider, despite that being bogus per the bindings themselves.
> >>
> >> Since there is some potential use in being able to map at least single
> >> input IDs to multi-cell output specifiers (and properly support 0-cell
> >> outputs as well), add support for properly parsing and using the target
> >> nodes' #cells values, albeit with the unfortunate complication of still
> >> having to work around expectations of the old behaviour too.
> >>
> >> Since there are multi-cell output specifiers, the callers of of_map_id()
> >> may need to get the exact cell output value for further processing.
> >> Added support for that part --charan
> >>
> >> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> >> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
> >> ---
> >> drivers/iommu/of_iommu.c | 3 +-
> >> drivers/of/base.c | 107 ++++++++++++++++++++++++++++++---------
> >> include/linux/of.h | 17 ++++---
> >> 3 files changed, 94 insertions(+), 33 deletions(-)
> >>
> >> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> >> index eac62bc441c5..48759cf1d900 100644
> >> --- a/drivers/iommu/of_iommu.c
> >> +++ b/drivers/iommu/of_iommu.c
> >> @@ -45,10 +45,11 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
> >> struct device *dev,
> >> const u32 *id)
> >> {
> >> - struct of_phandle_args iommu_spec = { .args_count = 1 };
> >> + struct of_phandle_args iommu_spec = {};
> >> struct of_map_id_arg arg = {
> >> .target = &iommu_spec.np,
> >> .id_out = iommu_spec.args,
> >> + .map_cells = &iommu_spec.args_count,
> >> };
> >> int err;
> >>
> >> diff --git a/drivers/of/base.c b/drivers/of/base.c
> >> index b8f78a9e6a09..68a7d6ddba66 100644
> >> --- a/drivers/of/base.c
> >> +++ b/drivers/of/base.c
> >> @@ -2045,11 +2045,30 @@ int of_find_last_cache_level(unsigned int cpu)
> >> return cache_level;
> >> }
> >>
> >> +/*
> >> + * Some DTs have an iommu-map targeting a 2-cell IOMMU node while
> >> + * specifying only 1 cell. Fortunately they all consist of length == 1
> >> + * entries with the same target, so check for that pattern.
> >
> > Can you show what a bad entry looks like here.
> >
>
> Sure, will add an example in the comments. Basically it would look like below.
>
> for iommu with iommu-cells = <2>;
>
> Device having below iommu-map property.
>
> iommu-map = <0x0000 &smmu 0x0000 0x1>,
> <0x0100 &smmu 0x0100 0x1>;
>
> >> + */
> >> +static bool of_check_bad_map(const __be32 *map, int len)
> >> +{
> >> + __be32 phandle = map[1];
> >> +
> >> + if (len % 4)
> >> + return false;
> >> + for (int i = 0; i < len; i += 4) {
> >> + if (map[i + 1] != phandle || map[i + 3] != cpu_to_be32(1))
> >
> > Why does the IOMMU arg cell have to be 1? The description said 'same
> > target', but it is just all have an IOMMU cell value of 1?
> >
>
> Here, the check is for length argument to be 1. This is to maintain backward
> compatibility as mentioned above, as all such bad entries right now have
> length as 1.
You say length and I think arg/cell length, not that the cell value
contains a length. That's because generally cell args are provider
defined and specific. So just say the 2nd cell has a value of 1 and
leave out that's a length.
[...]
> >> @@ -1455,7 +1456,7 @@ static inline int of_map_msi_id(const struct device_node *np, u32 id,
> >> .id_out = id_out,
> >> };
> >>
> >> - return of_map_id(np, id, "msi-map", "msi-map-mask", &arg);
> >> + return of_map_id(np, id, "msi-map", "#msi-cells", "msi-map-mask", &arg);
> >
> > There are cases of no #msi-cells and we default to 0 cells in that case.
> > Do you maintain that?
> >
> > Rob
>
> Thanks for pointing this, I see this case of no #msi-cells is not covered. Will
> add it in next revision. Also, IIUC shouldn't we set default cells to '1' to
> maintain backward compatibility of of_map_id in this case ? No ?
The only default is 0. Perhaps msi-map is never used if there are 0
cells? IDK, you tell me.
Rob
On 12/11/2025 2:34 AM, Rob Herring wrote:
> On Wed, Dec 10, 2025 at 03:57:56PM +0530, Vijayanand Jitta wrote:
>> On 12/10/2025 1:47 AM, Rob Herring wrote:
>>> On Thu, Dec 04, 2025 at 03:25:30PM +0530, Vijayanand Jitta wrote:
>>>> From: Robin Murphy <robin.murphy@arm.com>
>>>>
>>>> So far our parsing of {iommu,msi}-map properites has always blindly
>>>> asusmed that the output specifiers will always have exactly 1 cell.
>>>> This typically does happen to be the case, but is not actually enforced
>>>> (and the PCI msi-map binding even explicitly states support for 0 or 1
>>>> cells) - as a result we've now ended up with dodgy DTs out in the field
>>>> which depend on this behaviour to map a 1-cell specifier for a 2-cell
>>>> provider, despite that being bogus per the bindings themselves.
>>>>
>>>> Since there is some potential use in being able to map at least single
>>>> input IDs to multi-cell output specifiers (and properly support 0-cell
>>>> outputs as well), add support for properly parsing and using the target
>>>> nodes' #cells values, albeit with the unfortunate complication of still
>>>> having to work around expectations of the old behaviour too.
>>>>
>>>> Since there are multi-cell output specifiers, the callers of of_map_id()
>>>> may need to get the exact cell output value for further processing.
>>>> Added support for that part --charan
>>>>
>>>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>>>> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
>>>> ---
>>>> drivers/iommu/of_iommu.c | 3 +-
>>>> drivers/of/base.c | 107 ++++++++++++++++++++++++++++++---------
>>>> include/linux/of.h | 17 ++++---
>>>> 3 files changed, 94 insertions(+), 33 deletions(-)
>>>>
>>>> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
>>>> index eac62bc441c5..48759cf1d900 100644
>>>> --- a/drivers/iommu/of_iommu.c
>>>> +++ b/drivers/iommu/of_iommu.c
>>>> @@ -45,10 +45,11 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
>>>> struct device *dev,
>>>> const u32 *id)
>>>> {
>>>> - struct of_phandle_args iommu_spec = { .args_count = 1 };
>>>> + struct of_phandle_args iommu_spec = {};
>>>> struct of_map_id_arg arg = {
>>>> .target = &iommu_spec.np,
>>>> .id_out = iommu_spec.args,
>>>> + .map_cells = &iommu_spec.args_count,
>>>> };
>>>> int err;
>>>>
>>>> diff --git a/drivers/of/base.c b/drivers/of/base.c
>>>> index b8f78a9e6a09..68a7d6ddba66 100644
>>>> --- a/drivers/of/base.c
>>>> +++ b/drivers/of/base.c
>>>> @@ -2045,11 +2045,30 @@ int of_find_last_cache_level(unsigned int cpu)
>>>> return cache_level;
>>>> }
>>>>
>>>> +/*
>>>> + * Some DTs have an iommu-map targeting a 2-cell IOMMU node while
>>>> + * specifying only 1 cell. Fortunately they all consist of length == 1
>>>> + * entries with the same target, so check for that pattern.
>>>
>>> Can you show what a bad entry looks like here.
>>>
>>
>> Sure, will add an example in the comments. Basically it would look like below.
>>
>> for iommu with iommu-cells = <2>;
>>
>> Device having below iommu-map property.
>>
>> iommu-map = <0x0000 &smmu 0x0000 0x1>,
>> <0x0100 &smmu 0x0100 0x1>;
>>
>>>> + */
>>>> +static bool of_check_bad_map(const __be32 *map, int len)
>>>> +{
>>>> + __be32 phandle = map[1];
>>>> +
>>>> + if (len % 4)
>>>> + return false;
>>>> + for (int i = 0; i < len; i += 4) {
>>>> + if (map[i + 1] != phandle || map[i + 3] != cpu_to_be32(1))
>>>
>>> Why does the IOMMU arg cell have to be 1? The description said 'same
>>> target', but it is just all have an IOMMU cell value of 1?
>>>
>>
>> Here, the check is for length argument to be 1. This is to maintain backward
>> compatibility as mentioned above, as all such bad entries right now have
>> length as 1.
>
> You say length and I think arg/cell length, not that the cell value
> contains a length. That's because generally cell args are provider
> defined and specific. So just say the 2nd cell has a value of 1 and
> leave out that's a length.
>
> [...]
>
Understood, will update the comment as suggested.
>>>> @@ -1455,7 +1456,7 @@ static inline int of_map_msi_id(const struct device_node *np, u32 id,
>>>> .id_out = id_out,
>>>> };
>>>>
>>>> - return of_map_id(np, id, "msi-map", "msi-map-mask", &arg);
>>>> + return of_map_id(np, id, "msi-map", "#msi-cells", "msi-map-mask", &arg);
>>>
>>> There are cases of no #msi-cells and we default to 0 cells in that case.
>>> Do you maintain that?
>>>
>>> Rob
>>
>> Thanks for pointing this, I see this case of no #msi-cells is not covered. Will
>> add it in next revision. Also, IIUC shouldn't we set default cells to '1' to
>> maintain backward compatibility of of_map_id in this case ? No ?
>
> The only default is 0. Perhaps msi-map is never used if there are 0
> cells? IDK, you tell me.
>
> Rob
You are right, I’ve grepped through the upstream DTs that use msi-map
(Rockchip, TI K3, HiSilicon, QCom, NXP/Freescale, etc.), and I don’t
see any cases where provider uses msi-map while having #msi-cells = <0>
or omitting #msi-cells entirely.
All of the common MSI providers referenced by msi-map (GIC ITS, v2m,
etc.) define #msi-cells to 1.
So, I think the current patch should be fine as‑is, as there are no
upstream users of msi-map relying on a 0‑cell or missing #msi-cells
provider.
Thanks,
Vijay
Hi Vijayanand,
kernel test robot noticed the following build errors:
[auto build test ERROR on xen-tip/linux-next]
[also build test ERROR on v6.18]
[cannot apply to robh/for-next pci/next pci/for-linus linus/master next-20251204]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Vijayanand-Jitta/of-Add-convenience-wrappers-for-of_map_id/20251204-180719
base: https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next
patch link: https://lore.kernel.org/r/20251204095530.8627-4-vijayanand.jitta%40oss.qualcomm.com
patch subject: [PATCH v2 3/3] of: Respect #{iommu,msi}-cells in maps
config: i386-buildonly-randconfig-001-20251205 (https://download.01.org/0day-ci/archive/20251205/202512051124.ot03fX1c-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251205/202512051124.ot03fX1c-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512051124.ot03fX1c-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from kernel/sched/rq-offsets.c:5:
In file included from kernel/sched/sched.h:31:
In file included from include/linux/cpufreq.h:17:
>> include/linux/of.h:918:1: error: expected identifier or '('
918 | {
| ^
1 error generated.
make[3]: *** [scripts/Makefile.build:182: kernel/sched/rq-offsets.s] Error 1 shuffle=4056561518
make[3]: Target 'prepare' not remade because of errors.
make[2]: *** [Makefile:1280: prepare0] Error 2 shuffle=4056561518
make[2]: Target 'prepare' not remade because of errors.
make[1]: *** [Makefile:248: __sub-make] Error 2 shuffle=4056561518
make[1]: Target 'prepare' not remade because of errors.
make: *** [Makefile:248: __sub-make] Error 2 shuffle=4056561518
make: Target 'prepare' not remade because of errors.
vim +918 include/linux/of.h
0384e8c6c6fa49 Pantelis Antoniou 2015-01-21 914
c56888c32d643b Robin Murphy 2025-12-04 915 static inline int of_map_id(const struct device_node *np, u32 id, const char *map_name,
c56888c32d643b Robin Murphy 2025-12-04 916 const char *cells_name, const char *map_mask_name,
c56888c32d643b Robin Murphy 2025-12-04 917 struct of_map_id_arg *arg);
2a6db719c92dbf Nipun Gupta 2018-09-10 @918 {
2a6db719c92dbf Nipun Gupta 2018-09-10 919 return -EINVAL;
2a6db719c92dbf Nipun Gupta 2018-09-10 920 }
2a6db719c92dbf Nipun Gupta 2018-09-10 921
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Vijayanand,
kernel test robot noticed the following build errors:
[auto build test ERROR on xen-tip/linux-next]
[also build test ERROR on v6.18]
[cannot apply to robh/for-next pci/next pci/for-linus linus/master next-20251204]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Vijayanand-Jitta/of-Add-convenience-wrappers-for-of_map_id/20251204-180719
base: https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next
patch link: https://lore.kernel.org/r/20251204095530.8627-4-vijayanand.jitta%40oss.qualcomm.com
patch subject: [PATCH v2 3/3] of: Respect #{iommu,msi}-cells in maps
config: alpha-allnoconfig (https://download.01.org/0day-ci/archive/20251205/202512051121.ivp77JHU-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251205/202512051121.ivp77JHU-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512051121.ivp77JHU-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
In file included from include/linux/cpufreq.h:17,
from kernel/sched/sched.h:31,
from kernel/sched/rq-offsets.c:5:
>> include/linux/of.h:918:1: error: expected identifier or '(' before '{' token
918 | {
| ^
>> include/linux/of.h:915:19: warning: 'of_map_id' used but never defined
915 | static inline int of_map_id(const struct device_node *np, u32 id, const char *map_name,
| ^~~~~~~~~
make[3]: *** [scripts/Makefile.build:182: kernel/sched/rq-offsets.s] Error 1
make[3]: Target 'prepare' not remade because of errors.
make[2]: *** [Makefile:1280: prepare0] Error 2
make[2]: Target 'prepare' not remade because of errors.
make[1]: *** [Makefile:248: __sub-make] Error 2
make[1]: Target 'prepare' not remade because of errors.
make: *** [Makefile:248: __sub-make] Error 2
make: Target 'prepare' not remade because of errors.
vim +918 include/linux/of.h
0384e8c6c6fa49d Pantelis Antoniou 2015-01-21 914
c56888c32d643b3 Robin Murphy 2025-12-04 @915 static inline int of_map_id(const struct device_node *np, u32 id, const char *map_name,
c56888c32d643b3 Robin Murphy 2025-12-04 916 const char *cells_name, const char *map_mask_name,
c56888c32d643b3 Robin Murphy 2025-12-04 917 struct of_map_id_arg *arg);
2a6db719c92dbfe Nipun Gupta 2018-09-10 @918 {
2a6db719c92dbfe Nipun Gupta 2018-09-10 919 return -EINVAL;
2a6db719c92dbfe Nipun Gupta 2018-09-10 920 }
2a6db719c92dbfe Nipun Gupta 2018-09-10 921
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Vijayanand,
kernel test robot noticed the following build warnings:
[auto build test WARNING on xen-tip/linux-next]
[also build test WARNING on v6.18]
[cannot apply to robh/for-next pci/next pci/for-linus linus/master next-20251204]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Vijayanand-Jitta/of-Add-convenience-wrappers-for-of_map_id/20251204-180719
base: https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next
patch link: https://lore.kernel.org/r/20251204095530.8627-4-vijayanand.jitta%40oss.qualcomm.com
patch subject: [PATCH v2 3/3] of: Respect #{iommu,msi}-cells in maps
config: arm-allnoconfig (https://download.01.org/0day-ci/archive/20251205/202512051152.PJ6mf512-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project d8b43edf552840e59a22a7f3cc332697bd434782)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251205/202512051152.PJ6mf512-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512051152.PJ6mf512-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/of/base.c:2144:7: warning: variable 'cells' is used uninitialized whenever '&&' condition is false [-Wsometimes-uninitialized]
2144 | if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
| ^~~~~~~~
drivers/of/base.c:2149:30: note: uninitialized use occurs here
2149 | if (map_len - offset < 3 + cells)
| ^~~~~
drivers/of/base.c:2144:7: note: remove the '&&' if its condition is always true
2144 | if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
| ^~~~~~~~~~~
drivers/of/base.c:2125:30: note: initialize the variable 'cells' to silence this warning
2125 | u32 id_base, phandle, cells, id_len, id_off;
| ^
| = 0
1 warning generated.
vim +2144 drivers/of/base.c
2065
2066 /**
2067 * of_map_id - Translate an ID through a downstream mapping.
2068 * @np: root complex device node.
2069 * @id: device ID to map.
2070 * @map_name: property name of the map to use.
2071 * @cells_name: property name of target specifier cells.
2072 * @map_mask_name: optional property name of the mask to use.
2073 * @arg: contains the optional params, @target which is a pointer
2074 * to the target device node and id_out which is a pointer
2075 * to receive the translated ID.
2076 *
2077 * Given a device ID, look up the appropriate implementation-defined
2078 * platform ID and/or the target device which receives transactions on that
2079 * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
2080 * @id_out may be NULL if only the other is required. If @target points to
2081 * a non-NULL device node pointer, only entries targeting that node will be
2082 * matched; if it points to a NULL value, it will receive the device node of
2083 * the first matching target phandle, with a reference held.
2084 *
2085 * Return: 0 on success or a standard error code on failure.
2086 */
2087 int of_map_id(const struct device_node *np, u32 id, const char *map_name,
2088 const char *cells_name, const char *map_mask_name,
2089 struct of_map_id_arg *arg)
2090 {
2091 u32 map_mask, masked_id;
2092 int map_bytes, map_len, offset = 0;
2093 bool bad_map = false;
2094 const __be32 *map = NULL;
2095
2096 if (!np || !map_name || !arg || (!arg->target && !arg->id_out))
2097 return -EINVAL;
2098
2099 map = of_get_property(np, map_name, &map_bytes);
2100 if (!map) {
2101 if (arg->target)
2102 return -ENODEV;
2103 /* Otherwise, no map implies no translation */
2104 *arg->id_out = id;
2105 return 0;
2106 }
2107
2108 if (map_bytes % sizeof(*map))
2109 goto err_map_len;
2110 map_len = map_bytes / sizeof(*map);
2111
2112 /* The default is to select all bits. */
2113 map_mask = 0xffffffff;
2114
2115 /*
2116 * Can be overridden by "{iommu,msi}-map-mask" property.
2117 * If of_property_read_u32() fails, the default is used.
2118 */
2119 if (map_mask_name)
2120 of_property_read_u32(np, map_mask_name, &map_mask);
2121
2122 masked_id = map_mask & id;
2123 while (offset < map_len) {
2124 struct device_node *phandle_node;
2125 u32 id_base, phandle, cells, id_len, id_off;
2126 const __be32 *out_base;
2127
2128 if (map_len - offset < 2)
2129 goto err_map_len;
2130
2131 id_base = be32_to_cpup(map + offset);
2132 if (id_base & ~map_mask) {
2133 pr_err("%pOF: Invalid %s translation - %s (0x%x) ignores id-base (0x%x)\n",
2134 np, map_name, map_mask_name,
2135 map_mask, id_base);
2136 return -EFAULT;
2137 }
2138
2139 phandle = be32_to_cpup(map + offset + 1);
2140 phandle_node = of_find_node_by_phandle(phandle);
2141 if (!phandle_node)
2142 return -ENODEV;
2143
> 2144 if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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